Least k such that Sum_{i=1..k} gcd(k,i) = n * sigma(k).

Terms

a(0) =1a(1) =40a(2) =220a(3) =980a(4) =2940a(5) =11016a(6) =10080a(7) =44064a(8) =55080a(9) =112000a(10) =245344a(11) =220320a(12) =308448a(13) =484704a(14) =550368a(15) =2590720a(16) =38509344a(17) =1349460a(18) =3248000a(19) =7772160a(20) =2423520a(21) =5464480a(22) =51482340a(23) =14837760a(24) =6301152a(25) =18135040a(26) =19872864a(27) =10795680a(28) =61116768a(29) =45323520